In manufacturing a device of good quality with a high yield, improvements in degree of accuracy of a position alignment are extremely important. For example, even in a case where a device is manufactured with low costs by the use of an inkjet method, an improvement in the degree of accuracy of the position alignment is desirable.
When a device is manufactured, there is known an XY stage as a means for executing a position alignment of a substrate which is a middle body of the device with a processing apparatus for executing a process thereto (for example, Patent Documents 1 and 2). The XY stage includes, for example, a mechanism that moves a movable table with a substrate to be processed mounted thereon along an X direction, and a mechanism that moves a process portion with the process apparatus installed thereon along a Y direction. It is hereby possible to execute a predetermined process in a predetermined position of the substrate to be processed while changing and controlling the relative position of the substrate to be processed and the process apparatus in the X direction and the Y direction.
In order to control the position of the substrate to be processed with a high degree of accuracy in the XY stage, it is important to increase a degree of flatness of a mounting surface of the substrate to be processed in the movable table. As a method of increasing the degree of flatness, a method of polishing a mounting surface side or the like using a material with a high hardness, for example, granite or the like used in a surface plate or the like is considered. In addition, in order to reduce the process speed by moving the movable table at a high speed, or in order to decrease the running cost of the XY stage, a lightening of the movable table is also important. In particular, since the substrate tends to be large depending on the device to be manufactured, in order to be able to cope with a large substrate, lightening of the movable table is desirable. As a method of lightening the movable table, for example, there is considered a method in which a metal with superior workability is used as a material and the metallic material is partly thinned.    [Patent Document 1] Japanese Unexamined Patent Application, First Publication No. H07-311375    [Patent Document 2] Japanese Unexamined Patent Application, First Publication No. 2005-114882